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WOS: 000523425900003 This paper investigates the radiation shielding properties, such as linear and mass attenuation coefficients, half and tenth value layers, effective atomic number and electron density, and radiation protection efficiency as a function of photon energy, of a new composite, PbI2-doped polyester. The mentioned polyester composite was prepared with different proportions of lead(II) iodide (5% increments between 5 and 20%) so that impact of the dopant amount on radiation shielding could be properly analyzed. The prepared composites were tested in 22 different energies in the energy range of 59.5-1408.0 keV with the use of HPGe detector and eight radioactive point sources. The obtained results were further validated by comparing the results of XCOM computer program, and negligible discrepancies were observed. It was observed that PbI2 (20%) composite is more effective gamma radiation shielding material than other produced composites. In light of this information, it can be said that the shielding efficiency increases with increasing lead(II) iodide amount.

A tsunami warning system providing services in the Eastern Mediterranean, Aegean, Marmara and Black Seas under the UNESCO Intergovernmental Oceanographic Commission (IOC)—Intergovernmental Coordination Group (ICG) for the Tsunami Early Warning and Mitigation System in the North-Eastern Atlantic, the Mediterranean and Connected Seas (NEAMTWS) framework was established in Turkey by the Kandilli Observatory and Earthquake Research Institute (KOERI) (Özel et al., 2011). KOERI’s Regional Earthquake and Tsunami Monitoring Center (RETMC) was established on the foundations of the legacy KOERI National Earthquake Monitoring Center (NEMC) by adding observation, analysis and operational capability related to tsunami early warnings after an extensive preparatory period during 2009 and 2011. The center initiated its test-mode 7/24 operational status as a national tsunami warning center in 2011, and after a one year period it became operational as a candidate tsunami warning center for NEAMTWS on 1 July 2012, together with CENALT (Centre d’Alerte aux Tsunamis—France) and followed by the NOA (National Observatory of Athens—Greece) on 28 August 2012, INGV (Instituto Nazionale di Geofisica e Vulcanologia—Italy) on 1 October 2014 and IPMA (Instituto Português do Mar e da Atmosfera—Portugal) on 1 February 2018, completing full coverage of the tsunami-prone regions monitored by NEAMTWS. In this paper, an overview of the progress and continuous improvement of KOERI’s tsunami early warning system will be presented, together with lessons learned from important tsunamigenic events, such as the 20 July 2017 Bodrum–Kos Mw 6.6 and 30 October 2020 Samos–Izmir Mw 6.9 earthquakes. Gaps preventing the completion of an effective tsunami warning cycle and areas for future improvement are also addressed.

Durak, Ridvan/0000-0002-3935-176X; DURAK, RIDVAN/0000-0002-3935-176X; Akman, Ferdi/0000-0002-8838-1762 WOS: 000347578500013 The K shell absorption jump factors and jump ratios for La2O3, Ce and Gd samples have been determined using the gamma or X-ray attenuation and EDXRF methods. It is the first time that the K shell absorption jump factor and jump ratio have been discussed for present elements using two different methods. To detect K X-rays, a high resolution Si(Li) detector was used. The experimental results of K shell absorption jump factors and jump ratios were compared with the theoretically calculated ones. (C) 2014 Elsevier Ltd. All rights reserved. Ataturk University Research FundAtaturk University [2011/82] This work was done with the support of the Ataturk University Research Fund under Project no. 2011/82.

International Conference on Advances in Natural and Applied Sciences (ICANAS) -- APR 18-21, 2017 -- Antalya, TURKEY DURAK, RIDVAN/0000-0002-3935-176X; Akman, Ferdi/0000-0002-8838-1762 WOS: 000405093100083 The total mass attenuation coefficients (mu/rho), total molecular (sigma(t,m)), atomic (sigma(t,a)) and electronic (sigma(t,e)) cross sections, effective atomic numbers (Z(eff)) and electron density (N-E) were computed in the wide energy region from 1 keV to 100 GeV for the selected narcotic drugs such as morphine, heroin, cocaine, ecstasy and cannabis. The changes of mu/rho, sigma(t,m), sigma(t,a), sigma(t,e), Z(eff) and N-E with photon energy for total photon interaction shows the dominance of different interaction process in different energy regions. The variations of mu/rho, sigma(t,m), sigma(t,e), Z(eff) and N-E depend on the atom number, photon energy and chemical composition of narcotic drugs. Also, these parameters change with number of elements, the range of atomic numbers in narcotic drugs and total molecular weight. These data can be useful in the field of forensic sciences and medical diagnostic. Agri Ibrahim Cecen Univ, IC Fdn

Ofloxacin (OFL) loaded poly(e-caprolactone) (PCL) and PCL: poly(butylene succinate) PBS fibers as a drug delivery system in the treatment of ocular infections were prepared by electrospinning. In particular, the effect of some formulation variables including polymer:drug ratio (9:1, 8:2 and 7:3 w/w), solvent systems like dichloromethane (DCM), N,N-dimethylformamide (DMF), N,Ndimethylacetamide (DMAc) and dimethylsulfoxide (DMSO), polymer blends of PCL:PBS at 80:20, 60:40 and 40:60 ratios on fiber morphology, fiber size were investigated. The morphology and diameter of the electrospun fibers were investigated by scanning electron microscopy (SEM) images also the thermal properties were evaluated by differential scanning calorimetry (DSC). The drug release behaviour from fibers and in vitro antibacterial activity were also studied. It was noticed that the average fiber diameter decreased with decreasing polymer amount in initial composition meanwhile the release of drug increased with increasing amount of drug in formulations. Solvent system of DCM:DMF at 80:20 ratio improved fiber morphology and resulted in a reduction in fiber diameter. It was found that smooth surface, flexible fibers with uniform morphology were obtained with 80:20 ratio of PCL:PBS compositions. All fibers showed a burst release of OFL. The initial amount of the released OFL was found to vary as a function of PCL:OFL ratio and polymer composition in the fiber. The microbiological activity of optimized formulation was evaluated using P. aeruginosa, S. epidermidis, S. Aureus and E. coli strains and the results of this study clearly demonstrated that freely released OFL from fibers inhibited the growth of the tested bacteria. The process of electrospinning had no adverse effect on the activity of incorporated drug in fibers.

DURAK, RIDVAN/0000-0002-3935-176X; Durak, Ridvan/0000-0002-3935-176X; Akman, Ferdi/0000-0002-8838-1762 WOS: 000355889000016 PubMed: 25880612 The effective atomic numbers and electron densities of some samarium compounds were determined using the experimental total mass attenuation coefficient values near the K edge in the X-ray energy range from 36.847 up to 57.142 keV. The measurements, in the region from 36.847 to 57.142 keV, were done in a transmission geometry utilizing the K alpha(2), K alpha(1), K beta(1) and K beta(2) X-rays from different secondary source targets excited by the 59.54 keV gamma-photons from an Am-241 annular source. This paper presents the first measurement of the effective atomic numbers and electron densities for some samarium compounds near the K edge. The results of the study showed that the measured values were in good agreement with the theoretically calculated ones. (C) 2015 Elsevier Ltd. All rights reserved. Ataturk University Research FundAtaturk University [2011/82] This work was done with the support of the Ataturk University Research Fund under Project No(s). 2011/82.

In this work, L X-ray fluorescence cross sections, L sub-shell fluorescence yields and level widths and radiative vacancy transfer probabilities of L sub-shells to M i , N i and O i sub-shells were measured for the elements Ho, Lu, W, Hg and Bi. Energy dispersive X-ray fluorescence (EDXRF) technique was used to measure L X-ray photons. To obtain related parameters, we used 59.54 keV gamma photons of 241 Am radioactive point source. Emitted L X-ray photons from targets were collected by means of a Si(Li) detector with resolution of 180 eV at 5.9 keV. The present results are generally in a good agreement with theoretical calculations and the other results obtained in the literature, within their range considering experimental uncertainty.